Systems, methods, and apparatus for estimating power time of use

• US 9,003,063 B2
• Filed: 11/16/2011
• Issued: 04/07/2015
• Est. Priority Date: 11/16/2011
• Status: Active Grant

• Current Assignee: Aclara Meters LLC (Hubbell, Inc.)
• Original Assignee: General Electric Company
• Inventors: Ree, Bradley Richard, Bietz, Steven
• Primary Examiner(s): Abrishamkar, Kaveh
• Assistant Examiner(s): Kusyk, Janusz
• Application Number:
  US13/297,612
• Publication Number:
  US 20130124758A1
• Time in Patent Office: 1,238 Days
• Field of Search: None
• US Class Current: 709/248
• CPC Class Codes: G01D 2204/14 Displaying of utility usage with respect to time, e.g. for monitoring evolution of usage or with respect to weather conditions
• CPC Class Codes: G01D 4/002 Remote reading of utility meters
• CPC Class Codes: G01R 21/133 by using digital technique
• CPC Class Codes: G01R 22/063 related to remote communication
• CPC Class Codes: Y02B 90/20 Smart grids as enabling technology in buildings sector smart grids supporting the management or operation of end-user stationary applications in general, or like technologies with no associated climate change mitigation effect Y04S20/00
• CPC Class Codes: Y04S 20/30 Smart metering, e.g. specially adapted for remote reading

Abstract

Certain embodiments of the invention may include systems, methods, and apparatus for estimating power time of use. According to an example embodiment of the invention, a method is provided for synchronizing local system time with a network clock for estimating power time of use. The method includes storing power usage data and initial time stamps, wherein the initial time stamps are derived from one or more of a local clock or broadcast network time; receiving data comprising network time; adjusting the local system time with a PID loop, wherein the PID loop adjusts the local system time based at least in part on a difference between the local clock and the received network time; storing, with the power usage data and initial time stamps, an indicator when the difference is greater than a predetermined value; and determining synchronization when the difference is less than or equal to a predetermined value.

Claims

1. A method for estimating power time of use, the method comprising:

storing power usage data and local time stamps;

receiving data comprising network time;

adjusting the local system time with a proportional, integral, and derivative (PID) loop, wherein the PID loop adjusts the local system time based at least in part on a difference between a local clock and the received network time;

storing, with the power usage data and local time stamps, an indicator when the difference is greater than a predetermined error value;

determining synchronization has occurred when the difference is less than or equal to a predetermined synchronization value; and

revising one or more of the stored local time stamps after power loss and restoration when synchronization is determined, and associating and storing revised time stamp values with the power usage data, wherein revising comprises;

retrieving one or more local time stamps corresponding to the usage data;

detecting the power loss by subtracting a current time from a start time generating a resultant value;

determining the power loss has occurred if the resultant value is negative;

determining the power loss has occurred if the resultant value is greater than a predetermined interval; and

calculating one or more revised time stamp values, wherein the revised time stamp values have been adjusted with the PID loop.

2. The method of claim 1, wherein adjusting the local system time with the PID loop comprises removing jitter from the received network time.

3. The method of claim 1, wherein adjusting the local system time with the PID loop comprises adjusting the local system time with one or more of proportional feedback, proportional and integral feedback, or proportional, integral, and derivative feedback.

4. The method of claim 1, wherein time associated with the local clock is based at least in part on a signal associated with the power.

5. The method of claim 1, wherein storing the power usage data comprises integrating power usage over a first predetermined time period.

6. The method of claim 5, wherein storing the power usage data and time stamps comprises storing power usage data samples over a second predetermined time period greater than the first predetermined time period and associating the time stamps with the stored power usage data samples.

7. A system for estimating power time of use, the system comprising:

a network clock;

a local clock;

a proportional, integral, and derivative (PID) loop;

at least one memory for storing data and computer-executable instructions;

at least one processor configured to access the at least one memory, further configured to communicate with the network clock, the local clock, and the PID loop, and further configured to execute the computer-executable instructions for;

storing power usage data and local time stamps;

receiving data comprising network time from the network clock by one or more networks;

adjusting the local system time with the PID loop, wherein the PID loop adjusts the local system time based at least in part on a difference between the local clock and the received network time;

storing, with the power usage data and local time stamps, an indicator when the difference is greater than a predetermined error value;

determining synchronization has occurred when the difference is less than or equal to a predetermined synchronization value; and

revising one or more of the initial stored time stamps after power loss and restoration when synchronization is determined, and associating and storing revised time stamp values with the power usage data, wherein revising comprises;

retrieving one or more local time stamps corresponding to the usage data;

detecting the power loss by subtracting a current time from a start time generating a resultant value;

determining the power loss has occurred if the resultant value is negative;

determining the power loss has occurred if the resultant value is greater than a predetermined interval; and

calculating one or more revised time stamp values, wherein the revised time stamp values have been adjusted with the PID loop.

8. The system of claim 7, wherein adjusting the local system time with the PID loop comprises removing jitter from the received network time.

9. The system of claim 7, wherein adjusting the local system time with the PID loop comprises adjusting the local system time with one or more of proportional feedback, proportional and integral feedback, or proportional, integral, and derivative feedback.

10. The system of claim 7, wherein time associated with the local clock is based at least in part on a signal associated with the power.

11. The system of claim 7, wherein storing the power usage data comprises integrating power usage over a first predetermined time period.

12. The system of claim 11, wherein storing the power usage data and time stamps comprises storing power usage data samples over a second predetermined time period greater than the first predetermined time period and associating the time stamps with the stored power usage data samples.

13. An apparatus for estimating power time of use, the apparatus comprising:

a local clock;

a proportional, integral, and derivative (PID) loop;

at least one memory for storing data and computer-executable instructions;

at least one processor configured to access the at least one memory, further configured to communicate with the local clock and the PID loop, and further configured to execute the computer-executable instructions for;

storing power usage data and local time stamps;

receiving data comprising network time from the network clock;

adjusting the local system time with the PID loop, wherein the PID loop adjusts the local system time based at least in part on a difference between the local clock and the received network time;

storing, with the power usage data and local time stamps, an indicator when the difference is greater than a predetermined error value;

determining synchronization when the difference is less than or equal to a predetermined synchronization value; and

revising one or more of the initial stored time stamps after power loss and restoration when synchronization is determined, and associating and storing revised time stamp values with the power usage data, wherein revising comprises;

retrieving one or more local time stamps corresponding to the usage data;

detecting the power loss by subtracting a current time from a start time generating a resultant value;

determining the power loss has occurred if the resultant value is negative;

determining the power loss has occurred if the resultant value is greater than a predetermined interval; and

calculating one or more revised time stamp values, wherein the revised time stamp values have been adjusted with the PID loop.

14. The apparatus of claim 13, wherein adjusting the local system time with the PID loop comprises removing jitter from the received network time.

15. The apparatus of claim 13, wherein time associated with the local clock is based at least in part on a 60 Hz signal associated with the power.

16. The apparatus of claim 13, wherein storing the power usage data comprises integrating power usage over a first predetermined time period.

17. The apparatus of claim 16, wherein storing the power usage data and time stamps comprises storing power usage data samples over a second predetermined time period greater than the first predetermined time period and associating the time stamps with the stored power usage data samples.